Actually Apple doesn't allow traditional splash screens, check your iPhone human interface guidelines for clues.
Still we must transition from the PNG that is displayed as your application is started, to the point where your software
places something visually useful there. 

What happens is that the Default.png is painted on the screen as the app is loaded, when the applicationDidFinishLaunching: runs
you then have a chance to alter the view. 

The original Squeak.app would come up, then the screen would flash white as applicationDidFinishLaunching: ran, then black when 
the mainView morphic desktop was added, then fill with the actual morphic drawing as the Smalltalk code refreshed Display.


Tim had a thought of putting the splash screen as a image view in the Window so it appears as the Window nib is loaded, that 
avoids the white flash, then in your smalltalk code you remove the UIImage view.